Enterprises and organizations expose their business information and functionality on the web through software applications, usually referred to as “web applications.” Web applications provide great opportunities for an organization. Web applications use the Internet technologies and infrastructures. These applications are generally event-driven software programs which react to hyper text transfer protocol (HTTP) requests from the client. The applications are generally executed on application servers, constructed according to N-tier architecture, in which presentation, business logic, and data access layers are kept separate. Recently, web applications have evolved into large-scale applications that demand more sophisticated computing services.
FIG. 1 shows an exemplary data center 100 that is utilized for executing web applications. Data center 100 includes clients 110-1 through 110-N, web servers 120-1 through 120-M, application servers 130-1 through 130-Q, back-end systems 150, a load balancer 160, and a network 170. Clients 110 submit requests (e.g., HTTP requests) to web servers 120 through network 170. Load balancer 160 distributes the requests among the servers 120 to balance the load between servers 120 and 130. Each of web servers 120 dynamically generates presentation, for example, using servlets, or extensible markup language (XML), extensible style-sheet language (XSL), and the likes. Application servers 130 are often responsible for deploying and running the business logic layer and for interacting with and integrating various enterprise-wide resources, such as web servers 120, and back-end systems 150. The back-end system 150 may include, for example, a database and a legacy system.
Workload may be distributed across a cluster of application servers 130 in different ways. For example, application code may be replicated across multiple application servers in the cluster, enabling a given request to be processed by any of these multiple application servers 130. Also, application code may be logically partitioned over multiple application servers 130, e.g., so that a particular server 130 is responsible for performing particular types of operations. This type of application partitioning may improve the application performance. For example, data-intensive application logic may be configured to run on an application server that is closest to a data source, in order to reduce the latencies associated with accessing remotely located data.
As the web and application servers 120 and 130 become busier with handling more and more requests, the quality and level of service sharply decrease. With existing load balancing capabilities, once the servers are saturated, the quality of service drops drastically for all clients accessing a web site. Currently, a standard tool that automatically monitors, manages, and controls the operation and load of applications and servers is not found in the related art. The management and control of web applications mostly relies on technical personnel. This results with many drawbacks including unpredictable level of service and uncontrolled user experience as well as costly maintenance of applications. Additionally, the application management is static, i.e., the ability to detect problems and solve them in real-time is not feasible. Another major drawback is the inability to deliver services according to predefined service level agreements (SLAs), as the ability to provide committed services increasingly becomes a competitive requirement. Yet, another major drawback is the inability to balance the load differently per transaction in servers that are installed with multiple applications.
It would be therefore advantageous to provide a network solution for automatically managing and controlling web applications that overcome the drawbacks mentioned in the prior art.